Method of making finely-perforated ceramic plates



June 12, 1928. "1,673,269

J.- F. SCHEID ETAL METHOD OF MAKING FINELY' PERFORMED CERAMIC PLATES Filed July 15, 1926 a-- 1 d d Fig. 3

Patented June 12, 1928.

UNITED STATES PATENT. OFFICE.

JOHANN FRIEDRICH SGHEID, F HERMSDORF, AND VIK'IOR TONNDORF, 0F JENA, GERMANY, ASSIGNORS TO THE FIRM: CARL ZEISS, OF JENA, GERMANY.

METHOD or MAKING FINELY-IERFORATED CERAMIC PLATES.

Application filed July 18, 1926, Serial No. 122,214, and in Gcrmany January 24, 1925.

For various purposes, particularly for the manufacture of artificial fibres. e. g. artificial silk it is necessary to use plates with very fine openings. Suchplates may be used as filter plates, for instance. as sieve-plates for filtering the spinning material in the manufacture of artificial silk, or theopenings of such a plate form the nozzles through which the spinning material is squirted. To replace the metal plates customary for these purposes by ceramic plates proved difficult.

because it was not possible to make in a simple way plates which with regard to the quality of the execution of the holes satisfy the high demands which one is bound to make.

According to the present invention these plates are made in such a way'that one forms the respective plate of ceramic material and provides the still plastic plate with the desired holes by piercing the plate. Inorder to attain that in the finished plate the holes have exactly the desired shape up to their extremity one suitably does not entirely pierce the plastic plate but only sticks into it, hardens it (e. g. by burning) after the sticking-in and then removes the unpierced part pf the plate. By means of steel needles it is thus possible to make holes of exceeds ingly small diameter (smaller than 02mm.) which according to their shape and size exactly meetv the requirements.

The accmnpanying drawing shows an example of the invention. Fig. I shows a longitudinal section through a semi-finished spinning nozzle, Fig. 2 shows the appertaining plan, Fig. 3 shows the finished spinning nozzle in a longitudinal" section.

Into the bottom of a body a, moulded of still plastic porcelain material, holes d are 4 made with the aid of.needles b, which are fixed in a head a, in such away as not to pass through the bottom (see Fig. 1). Thereupon the body is burnt and the bottom Worked ofl' corresponding to the line X X. Thereby one obtains the finished spinning nozzle as shown in Fig. 3.

We claim Method of making finely perforated eeramic plates, consisting in this that a. plate of ceramic material is moulded, thereupon holes stuck into the plate, which do not. entirely traverse the plate, then the plate hardened and finally the part of the plate not traversed by the holes removed.

. JOHANN FRIEDRICH SCHEID.

VIKTOR TONNDORF. 

